写个最暴力的记忆化搜索爽一下

from sys import stdin,stdout,setrecursionlimit
from math import *
from functools import *
input = stdin.readline
print = stdout.write

n,m = map(int,input().split())
setrecursionlimit(1000000)
@lru_cache(maxsize=100000)
def dfs(x,y):
    if x == 1 and y == 1:
        return 1
    if x == 1:
        return dfs(x,y-1)
    if y == 1:
        return dfs(x-1,y)
    return (dfs(x-1,y)+dfs(x,y-1))%1000000007

print(str(dfs(n,m)))